Since I neglected to mention it before, I'm trying to get a hawaiin blue spotted boxfish to eat. He's been here for two months and hasn't eaten a single thing I have offered, luckily my tank is very established and had plenty of sponge and tunicates to feed from. I've tried almost everything to entice feeding with no luck. I have the orange and yellow sponges from the Carribean but he seems to not be interested in those at all, only the white sponge that grows naturally in the tank. If I knew a place that sold that or tunicates I would just buy them but I haven't had any luck finding someone who sells that. So that is where this question derived from.
I picked up some Hikari mega marine and no luck, just looked at it. Today I got a bottle of Brightwell Angelixir, it's a food soak specifically for spongivorous so we'll see if that works. Fingers crossed. I'm honestly surprised he hasn't died yet, he's been super skinny since I got him. Supplier told me he was eating mysis at his place in Hawaii... Ya right! Poor guy actually spent an extra day in shipping due to airplane issues, when I got him I thought he would die soon because his bounyancy was off and he just kept spinning in fast little circles. He's fine now, acts completely normal just refuses to eat.